Tobacco manipulating machines



Jan. 5, 1965 F. A. M. LABBE TOBACCO MANIPULATING MACHINES 5 Sheets-Sheet 1 Filed May 51, 1961 M [11 2 52 m 54 mad/w &

ATTORNEYd Jan. 5, 1965 F. A. M. LABBE 3,164,158

TOBACCO MANIPULATING MACHINES Filed May 51, 1961 5 Sheets-Sheet 2 Fig 2.

l4 \7 V A3 A \I-ML W A TTOR/VEX Jan. 5, 1965 F. A. M. LABBE TOBACCO MANIPULATING MACHINES 3 Sheets-Sheet 3 Filed May 51, 1961 United States Patent Claims priority, application Great Britain, Jane 21, M60,

21,715/60 4 Claims. e1. l3l84) This invention concerns improvements in or relating to a cigarette making machine in which a tobacco filler is formed on a flat air-pervious conveyor band and is held to the band by suction applied through the conveyor band.

An example of such a machine is disclosed in US. Patent No. 3,030,965, granted April 24, 1962, wherein tobacco particles are fed into a passage which extends to a perforated conveyor band, and a high velocity air stream is caused to flow through the passage so as to carry the tobacco particles to the conveyor. A suction chamber extending along the conveyor band draws air through the conveyor.

The invention is applied to a cigarette making machine in which a tobacco filler is formed on a flat air-pervious conveyor band by means of an air stream flowing through a passage toward the conveyor and which is drawn through the conveyor by suction so that the filler .is held to the surface of the band by air pressure, and having side guides forming a trough through which the conveyor and the filler move, and consists in grooves in the side guides extending lengthwise of the trough and adapted to modify the movement of particles toward the band surface by intercepting-some of them, whereby the aggregation of particles on the bands is affected.

In a modified construction the juncture between the band and the grooved side guides may have fillets fitted therein so that the surface of the filler near to the band consists of a central flat portion with two sides extending from the edges of the flat portion at an angle of less than 180 and such a fillet may have the section of a triangle with two 45 angles.

Where grooves are employed these may be of quite small size, for example /2 mm. deep, and are preferably so shaped that each guide has a section which is substantially that of an Acme thread.

Apparatus in accordance with the invention will now be described by way of example with reference to the accompanying drawings, in which:

FIGURE 1 is a side elevation partly in section of part of a continuous rod cigarette-making machine incorporating a trough according to the present invention;

FIGURE 2 is a fragmentary view showing a section on the line 22 of FIGURE 1 and drawn to a larger scale;

FIGURE 3 is a fragmentary view showing a section on the line 3-3 of FIGURE 1 and drawn to a larger scale;

FIGURE 4 is a fragmentary view showing a section of a trough illustrating a modification; and

FIGURE 5 is a cross-section of a wrapped filler made on a machine of the same class but not incorporating the invention,

FIGURE 6 is a cross-section on a line to agree with line 66, FIGURE 1, in the direction of the arrows but showing guides which will provide a cigarette having a section such as that shown in FIG. 5, and

FIGURE 7 is a cross-section on a line to agree with line 77, FIGURE 1, in the direction of the arrows but showing guides which will provide a cigarette having a section such as that shown in FIG. 5.

The apparatus shown in FIGURE 1 forms part of a continuous rod cigarette-making machine which is basically similar to the machine disclosed in US. Patent No. 3,030,965, referred to above.

Referring to FIGURE 1, the apparatus comprises a flat perforated metal conveyor band 1 arranged to movein the direction shown by the arrow, beneath a suction chamger 2 which draws air upwardly through the conveyor and.

A passage formed by side walls 3 and end walls 4 and 5 extends upwardly towards the band 1. Means (not shown) are provided to supply air to the lower end of the passage, and the arrangement is such that air flows up the passage in a continuous stream at high velocity. Tobacco-feeding means (not shown) are arranged to feed tobacco particles into the passage in such a way that they are impelled upwardly at high velocity to the band 1 by the air stream, and build up on the band to form a filler.

Some of the air which flows up the passage is drawn off through a perforated, louvered plate 6 by suction means.

Both the band 1 and the suction chamber 2 extend a substantial distance beyond the end wall 4 of the passage, that is to the left of the wall 4 as viewed in FIGURE 1, and air is drawn through that part of the band from atmosphere. This enables the tobacco filler which has been built up on the band in the passage to be held suctionally on the underside of the band I. A trimming device is provided to remove surplus tobacco from the tobacco filler. This device comprises a pair of cooperating discs 7 (one of which is visible in FIGURE 1) arranged beneath the band 1. Beyond the trimming device, the band 1 extends over a paper web 8, on to which the tobacco filler is led while still suctionally held on the band 1. When suction is cut off from the band, the filler is released and is thereafter conveyed by the paper web, which is then wrapped around it in the conventional manner to form a continuous wrapped rod.

The band 1 runs along a trough formed by side guide members 9 and It which form upward extensions of the walls 3, as shown in FIGURE 2. The band runs on a strip 13 of suitable hard-wearing material which is recessed, as shown in FIGURES 2 and 3 to form shoulders engaging the edge portions of the band I. The strip is fitted in rails 14 fixed on top of the members 9 and 10. The guides 9 and 10 are, to the left of the end walls 4 as viewed in FIGURE 1, recessed at 15 (as shown in chain lines in FIGURE 3) to provide an enlarged portion of the trough. Between the recessed parts of the side guide members is mounted a rotatable closure device or wheel 12. g

The tobacco filler when fully built up on the band I, and when carried by the latter out of the passage past the end wall 4, usually extends downwardly from the band a short distance into the widened portion of the trough, that is, between the recessed parts 15 of the side guides.

The rotatable wheel 12 comprises a hub portion provided with fourteen flat paddles or blades equally spaced around the periphery of the hub and inclined outwards at equal angles. The outer ends of the paddle elements are shaped so as to fit the local cross-section of the side guides 9 and the widths of the paddle elements are such as to fit closely between the guide members 9.

The wheel 12 is driven mechanically and each paddle as it reaches the topmost part of its travel lightly contacts the filler. In addition, the paddle of the lower part of the wheel at any instant engages closely with the interior of a housing 21 and this housing seals the end wall 4. Therefore the gap between the filler and the end wall 4 is substantially closed, at least to a sufiicient extent to prevent any serious flow of air into the passage from outside.

It will be seen from FIGURES 1 to 3 of the drawings that the opposed faces of the trough walls 9 and 10 are grooved lengthwise to provide small recesses and ribs. The wall surface has some elfect on the build-up of the filler on the porous band 1 as will now be explained.

If the walls are smooth as shown in FIGURES 6 and 7,

faces.

the band, andpartly. by the sustained air pressure to which this part of the filler is subjected, since it is on the band for a longer time than lower parts of'the filler, and the filler therefore builds up with varying density as indicated in FIGURES 6 or 7,.where the darker parts indicate high density. The dense parts hinder the passage of 'the air through" the filler and the heat thus generated ,cau'ses local drying of the tobacco, mainly in the neighborhood of-the band.

A further defect is shown diagrammatically in FI G- .URE 5. Because the upper part of the filler is fairly hard, itresists the reshaping of the filler to the circular form when thefiller is drawn through the rod forming apparatus of the 'machine and tends ,tosqueeze the less dense parts rather than to alter its own shape. Furthermore, the trimming operation shown in FIGURE 7 makes the lower part of the filler roughly convex in shape, as

the trimmers 7 do not cut tobacco but'only separate it, and

although the final rod is only about half the cross-sectional area of the filler when it is between the guides 9-10, the fact that the lower part of the filler is rounded by trimming makes it less resistant to pressure than if it had-square corners. The result is that the top of the filler in FIGURE is not tightly packed against the paper wrapper and a slight softness can be felt in the finished rod.

The purpose of the grooved surface is to give the successive particles reaching the band an opportunity to bridge the trough and thus to relieve the particles deposited earlier from some of the pressure. Furthermore,

particles striking the grooved parts will be deflected from ,their existing path to some extent and the build-up of the filler on the band will be affected in that the density of the filler will be maintained uniformly throughout. As the grooves run lengthwise of the guides, they will interfere with shreds passing toward the filler being formed on the band but they will not hinder the smooth passage of the built-up filler along the trough.

The groovesmay be about 0.5 mm. deep with the tops and bottoms as small as 0.1 mm. wide. 7

Referring now to FIGURE 4, the aggregation of the particles on the band is further affected by fitting fillets Zll in the corners to limit the band width. The filler will form as usual because of the suction and tobacco will be held adjacent the fillets; The top of the filler will conform to the shape defined by the band and the fillet sur- Such a shape approaches the shape this part of the filler will take when compressed to the final rod shape snasnas and size. The fillets could, if desired, be of other crosssections, for example the operative faces could be concave arcs.

What I claim as my invention and desire to secure by Letters Patent is:

1. In a cigarette making machine. the improvement comprising Wallsforming a passage through which flows an air stream having tobacco particles entrained therein, an elongated fiat, air pervious conveyor band traversing said pasasge generally normal to the flow of said air stream, said conveyor intercepting the flowing particles in said stream at one end of said passage to build up on said conveyor band a tobacco filler, a suction source communicating with said passage through said pervious conveyorto hold the thus-formed filler to the band surface by air pressure, the end of said passage adjacent the band including side guides defining a tobacco filler-receiving trough with said band, the surfaces of said side guides being formed with alternating lands and grooves extending lengthwise of said trough, said lands and grooves modifying the flow of particles in the vicinity of the band to improve the uniformity of said filler on said band and serving to guide the formed filler as said conveyor leaves said passage.

2. In a cigarette making machine as in claim 1 wherein the filler-contacting surface of said band and the surfaces of the immediately proximate portions of said side guides intersect at generally obtuse angles.

3. In a cigarette making machine as in claim 1 wherein substantially triangular solid fillets are arranged in the corners of said trough immediately proximate said band surface, the exposed faces of said fillets extending at an angle of less than relative to the band surface.

4. A cigarette making machine as claimed in claim 1 wherein each guide has a section which is substantially that of an Acme thread having a depth of approximately /2 mm.

References Cited by the Examiner UNITED STATES PATENTS 2,103,721 12/37 Herrmann 13166 2,164,423 7/39 Podmore 131-66 2,660,177 11/53 Rault 13l66 2,697,474 12/54 McGinley.

FOREIGN PATENTS 1,179,992 12/58 France.

8,877 1901 Great Britain.

ABRAHAM G. STONE, Primary Examiner.

JOSEPH S. REICH, Examiner. 

1. IN A CIGARETTE MAKING MACHINE, THE IMPROVEMENT COMPRISING WALLS FORMING A PASSAGE THROUGH WHICH FLOWS AN AIR STREAM HAVING TOBACCO PARTICLES ENTRAINED THEREIN, AN ELONGATED FLAT, AIR PERVIOUS CONVEYOR BAND TRAVERSING SAID PASSAGE GENERALLY NORMAL TO THE FLOW OF SAID AIR STREAM, SAID CONVEYOR INTERCEPTING THE FLOWING PARTICLES IN SAID STREAM AT ONE END OF SAID PASSAGE TO BUILD UP ON SAID CONVEYOR BAND A TOBACCO FILLER A SUCTION SOURCE COMMUNICATING WITH SAID PASSAGE THROUGH SAID PERVIOUS CONVEYOR TO HOLD THE THUS-FORMED FILLER TO THE BAND SURFACE BY AIR PRESSURE, THE END OF SAID PASSAGE ADJACENT THE BAND INCLUDING SIDE GUIDES DEFINING A TOBACCO FILLER-RECEIVING TROUGH WITH SAID BAND, THE SURFACES OF SAID SIDE GUIDES BEING FORMED WITH ALTERNATING LANDS AND GROOVES EXTENDING LENGTHWISE OF SAID TROUGH, SAID LANDS AND GROOVES MODIFYING THE FLOW OF PARTICLES IN THE VICINITY OF THE BAND TO IMPROVE THE UNIFORMITY OF SAID FILLER ON SAID BAND AND SERVING TO GUIDE THE FORMED FILLER AS SAID CONVEYOR LEAVES SAID PASSAGE. 